Curable flame retardant compositions with halogens have been used in printed circuit boards (PCBs). Glass fiber cloth laminates made from these compositions have excellent properties including low dielectric constants and dissipation factors. Products using these compositions also have higher toughness than typical epoxy glass laminates which have been used in PCBs.
Many of the compositions currently in use in printed circuit boards use brominated chemicals as flame retardants. Bromine, and other halogens, can generate dioxin during burning. Dioxin is very harmful to mammals, having an LD50 about 0.022 mg/kg when administered orally to rats. In addition, substantial amounts of the halogen may be required to impart flame retardancy to the printed circuit board.